02/12/2020
How do these mutations work?
The mutations were found in the instructions for the intricate "scaffolding" that organizes the inside of the body's cells, called the cytoskeleton.
Similar mutations that change the cytoskeleton in snails have been shown to lead mollusks to have a counterclockwise or "left-handed" shell.
Image copyright University of Nottingham Image caption Jeremy, the "left-handed" snail and one of its young
Remember the partner search for Jeremy, the "left-handed" garden snail because, in the snail world, right-handers and left-handers can't have sex since their genitals are in the wrong place when it comes to each other ? Finally they found a "left-handed" conch and they had 56 snails, although they all turned out to be "right-handed".
Scans of participants in the Biobank project showed that the cytoskeleton changed the structure of white matter in the brain.
"For the first time in humans, we have been able to establish that these cytoskeletal differences associated with the dominant hand are really visible in the brain," said Professor Douaud, who is left-handed.
In left-handed participants, the left and right hemispheres were better connected and more coordinated in the regions involved in language.
The researchers speculate that left-handed people may have better verbal skills, although this study does not provide the data to prove it.
The research also showed a slightly higher risk of schizophrenia and a slightly lower risk of Parkinson's disease in left-handed people.